Lesson Notes By Weeks and Term v5 - Grade 10

Lesson Video

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Performance objectives

• Describe and explain various types of pollution (air, water, and soil).
• Analyze the impacts of human activities on South African ecosystems.
• Explain the concept of biodiversity loss.
• Discuss sustainable practices to mitigate negative impacts.
• Evaluate the role of individuals and government in conservation.

Lesson summary

South Africa is a country blessed with incredible biodiversity, from the fynbos of the Western Cape to the savanna of the Kruger National Park.

However, our natural resources are under increasing pressure from human activities. Understanding the impact we have on our environment is crucial for ensuring a sustainable future for ourselves and future generations. This week, we delve deeper into the consequences of human actions and explore potential solutions to protect our environment. From water scarcity impacting farming communities to air pollution affecting urban populations, these are issues we face daily.

Lesson notes

2.1 Types of Pollution Pollution refers to the contamination of the environment with harmful substances.

We will focus on three main types: Air Pollution: The introduction of particles, biological molecules, or other harmful materials into Earth's atmosphere, causing diseases, allergies, death to humans, damage to other living organisms such as animals and food crops, or damage to the natural or built environment.

Sources: Industrial emissions: Factories releasing gases like sulfur dioxide (SO2), nitrogen oxides (NOx), and particulate matter. In South Africa, coal-fired power plants are a major source.

Example: The industrial areas in Gauteng, particularly around Sasolburg, contribute significantly to air pollution.

Vehicle exhaust: Cars, trucks, and buses releasing carbon monoxide (CO), NOx, and particulate matter. The high volume of traffic in major cities like Johannesburg and Cape Town contributes to this.

Burning of fossil fuels: For heating, cooking, and electricity generation. Many households in informal settlements rely on burning wood or coal, leading to indoor and outdoor air pollution.

Mining activities: Dust and particulate matter released during extraction and processing of minerals, especially in areas like the platinum belt in North West province.

Agricultural practices: Ammonia emissions from fertilizers and livestock waste.

Burning of waste: Informal burning of refuse, releasing toxic fumes.

Impacts: Respiratory illnesses: Asthma, bronchitis, lung cancer. Especially impacting children and the elderly.

Acid rain: SO2 and NOx react with water in the atmosphere to form acid rain, which damages vegetation and aquatic ecosystems.

Climate change: Greenhouse gases like carbon dioxide (CO2) trap heat in the atmosphere.

Smog: Reduced visibility and respiratory problems.

Water Pollution: The contamination of water bodies, usually as a result of human activities, in such a manner that negatively affects its legitimate uses.

Sources: Industrial discharge: Factories releasing chemicals, heavy metals, and other pollutants into rivers and streams.

Example: Textile factories in KwaZulu-Natal sometimes discharge dyes and other chemicals into local rivers.

Agricultural runoff: Fertilizers, pesticides, and animal waste washing into water bodies. This is particularly problematic in areas with intensive farming.

Sewage and wastewater: Untreated or poorly treated sewage contaminating water sources. This is a major problem in many South African towns and cities due to aging infrastructure and inadequate treatment facilities.

Mining activities: Acid mine drainage (AMD) from abandoned mines polluting water sources with heavy metals and sulfates. The Witwatersrand area is severely affected by AM

D. Oil spills: Leakage of oil into oceans and rivers from tankers and pipelines.

Litter: Plastic and other waste entering waterways.

Impacts: Waterborne diseases: Cholera, typhoid, dysentery. Particularly affecting communities relying on untreated water sources.

Eutrophication: Excessive nutrients from fertilizers causing algal blooms, which deplete oxygen and kill aquatic life.

Bioaccumulation: Pollutants accumulating in the tissues of organisms, posing a threat to human health through the food chain.

Damage to aquatic ecosystems: Killing fish, plants, and other organisms.

Contamination of drinking water: Making water unsafe for human consumption.

Soil Pollution: The contamination of soil with harmful substances, leading to degradation of soil quality and ecosystem health.

Sources: Industrial waste: Disposal of hazardous waste in landfills and uncontrolled sites.

Agricultural practices: Overuse of fertilizers and pesticides, leading to accumulation of chemicals in the soil.

Mining activities: Heavy metals and other pollutants from mining operations contaminating the soil.

Sewage sludge: Application of sewage sludge as fertilizer, which can contain heavy metals and pathogens.

Oil spills: Leakage of oil into the soil.

Acid Rain: Contaminating the soil with acids.

Improper Waste Disposal: In landfills, the soil becomes contaminated with leacheate.

Impacts: Contamination of food crops: Plants absorbing pollutants from the soil, posing a threat to human health.

Groundwater contamination: Pollutants leaching into groundwater sources.

Reduced soil fertility: Making it difficult to grow crops.

Damage to soil organisms: Affecting the health of the soil ecosystem.

Loss of biodiversity: Reduction in the number and variety of organisms living in the soil. 2.2 Impacts of Human Activities on South African Ecosystems South Africa's ecosystems are under significant pressure from various human activities.

Agriculture: Impacts: Deforestation: Clearing of natural vegetation for farmland, leading to habitat loss and soil erosion.

Soil erosion: Overgrazing and unsustainable farming practices leading to the loss of topsoil.

Water pollution: Runoff of fertilizers and pesticides contaminating water sources.